In a firearm of the automatic, semiautomatic or manual-repetition type having a magazine, when the cartridge moves from the magazine to the firing chamber it must execute a sort of jump entailing a change of position and orientation. The first cartridge of the magazine is aligned with an axis which is approximately parallel to the axis of the barrel, but somewhat lower. This allows a casing of a spent cartridge to be extracted from the firing chamber past the fresh cartridges below it in the clip. For this reason in the firearms of the known kind the cartridge following the spent and expelled one is pushed by the breech block or slide against an inclined surface whose purpose is to guide the fresh cartridge laterally to the firing chamber.
During this loading the cartridge is in effect almost wholly out of contact with the edges of the magazine and is not yet received and stabilized in the firing chamber. Thus this precariously held cartridge can get misaligned and jam the weapon with serious consequences for the user.